Understanding reaction products of granular and fluid P fertilisers in Australian soils: a way to enhance fertiliser efficiency. Despite posing significant challenges for crop P nutrition, alkaline soils are widespread in Australia and their agricultural use accounts for a significant fraction of the crop production nationwide. The benefits of fluid fertilizers over conventional granular products in these soils has been agronomically demonstrated. Knowledge of the behaviour of these products, pr ....Understanding reaction products of granular and fluid P fertilisers in Australian soils: a way to enhance fertiliser efficiency. Despite posing significant challenges for crop P nutrition, alkaline soils are widespread in Australia and their agricultural use accounts for a significant fraction of the crop production nationwide. The benefits of fluid fertilizers over conventional granular products in these soils has been agronomically demonstrated. Knowledge of the behaviour of these products, provided through an understanding of the fundamental mechanisms and reactions occurring, is critical to improve crop productivity. This project aims to study the reactions of fluid and granular fertilizers in soils using advanced spectroscopic and isotopic techniques, in order to provide a scientific basis for improving formulations and effectiveness.Read moreRead less
Links between carbon and nitrogen cycling processes in forest soils: An innovative approach with both NMR and stable isotope techniques. Understanding the critical links between soil carbon and nitrogen cycling processes in forest ecosystems is necessary for developing effective site management to enhance forest productivity and environmental benefits. In the first application of 14N-nuclear magnetic resonance (NMR) to soil humic acid (HA), we have discovered that surprisingly nitrate-N is prese ....Links between carbon and nitrogen cycling processes in forest soils: An innovative approach with both NMR and stable isotope techniques. Understanding the critical links between soil carbon and nitrogen cycling processes in forest ecosystems is necessary for developing effective site management to enhance forest productivity and environmental benefits. In the first application of 14N-nuclear magnetic resonance (NMR) to soil humic acid (HA), we have discovered that surprisingly nitrate-N is present in soil HAs, with the HA-nitrate N extremely sensitive to forest management practices. This project represents the first attempt to integrate the use of advanced NMR and stable isotope techniques to examine both chemical and biological linkages between carbon and nitrogen cycling processes in Australian and US forest ecosystems.Read moreRead less
The dynamics of organic matter turnover in soils to improve the productivity of Australia's agricultural industries. Two recent national reports on the soils issues facing Australian agriculture (Reeves et al, 1997; CSIRO, 2000) concluded that soil structural degradation remains, after salinisation, our major threat to the sustainability of agricultural production. This research will provide fundamental understanding of how the dynamics of organic matter turnover benefit aggregate formation and ....The dynamics of organic matter turnover in soils to improve the productivity of Australia's agricultural industries. Two recent national reports on the soils issues facing Australian agriculture (Reeves et al, 1997; CSIRO, 2000) concluded that soil structural degradation remains, after salinisation, our major threat to the sustainability of agricultural production. This research will provide fundamental understanding of how the dynamics of organic matter turnover benefit aggregate formation and stability. This will advance the understanding of organic matter from simply considering the quantity of carbon present, to one of predicting the short- and long-term benefits to soil structure. This approach is innovative in the study of soil health, and has the potential to greatly advance the development of conservation farming systems.Read moreRead less
Vineyard soil health and microbial biodiversity under different cover crop and floor management practices. This project will examine vineyard ?soil health? by monitoring the populations of soil microorganisms under different vineyard cultural practices, with an emphasis on microbial populations capable of suppressing soil borne disease and of increasing the nutrient uptake by the vine. The project will identify vineyard cover crop and floor management practices for the improvement of soil healt ....Vineyard soil health and microbial biodiversity under different cover crop and floor management practices. This project will examine vineyard ?soil health? by monitoring the populations of soil microorganisms under different vineyard cultural practices, with an emphasis on microbial populations capable of suppressing soil borne disease and of increasing the nutrient uptake by the vine. The project will identify vineyard cover crop and floor management practices for the improvement of soil health and sustainability in the rapidly expanding wine industry, providing considerable economic and environmental advantages to regional and rural communities.Read moreRead less
The potential of biosolids and flyash mixtures for soil remediation for revegetation of degraded land. Revegetation of land that has been subjected to land clearing or mining is often limited by the poor quality or lack of topsoil. It may prove possible to remediate these areas of land by incorporating a mixture of two waste products, biosolids and flyash. The aim in this project is to determine the usefulness of this method of land remediation by investigating the nutrient levels and fate of co ....The potential of biosolids and flyash mixtures for soil remediation for revegetation of degraded land. Revegetation of land that has been subjected to land clearing or mining is often limited by the poor quality or lack of topsoil. It may prove possible to remediate these areas of land by incorporating a mixture of two waste products, biosolids and flyash. The aim in this project is to determine the usefulness of this method of land remediation by investigating the nutrient levels and fate of contaminants in various mixtures of biosolids and flyash materials, in the absence and presence of soil minerals, and soil ameliorants such as fertilizers and gypsum.Read moreRead less
Conservation tillage and its potential to affect catchment salt and water balances. Replacement of deep-rooted vegetation with shallow rooted crops has resulted in greater movement of water into groundwater systems, raising in groundwater level and mobilizing salt to the land's surface. The practice of conservation tillage, provides a range of advantages to landholders, but also has the potential to accentuate the risk of salinisation because it increases water infiltration into the soil surfac ....Conservation tillage and its potential to affect catchment salt and water balances. Replacement of deep-rooted vegetation with shallow rooted crops has resulted in greater movement of water into groundwater systems, raising in groundwater level and mobilizing salt to the land's surface. The practice of conservation tillage, provides a range of advantages to landholders, but also has the potential to accentuate the risk of salinisation because it increases water infiltration into the soil surface. This project aims to evaluate the impact of conservation tillage on soil salt profiles in the Condamine-Balonne and Border Rivers Catchments, and to model will the effect of changed landscape salt and water balances on river water quality.Read moreRead less
Explaining the interactions between drought and fertiliser use efficiency using tracing and imaging techniques. With climate change, Australian agriculture is faced with periods of increasing drought and changing rainfall patterns. At the same time, Australian farmers are faced with increasing costs of fertiliser inputs (their largest variable input cost), yet have little information on how they should change their nutrient management programs to suit the changing climatic conditions. This proje ....Explaining the interactions between drought and fertiliser use efficiency using tracing and imaging techniques. With climate change, Australian agriculture is faced with periods of increasing drought and changing rainfall patterns. At the same time, Australian farmers are faced with increasing costs of fertiliser inputs (their largest variable input cost), yet have little information on how they should change their nutrient management programs to suit the changing climatic conditions. This project aims to determine the effect of drought and rainfall patterns on the efficiency of fertiliser use by crops, through examination of the effects of soil moisture conditions on the interaction between soil and added fertilisers. Read moreRead less
Synchronising phosphorus fertilisation with plant phosphorus demand: a tactic to reduce phosphorus transfer from land to water. Phosphorus loss from intensive pasture systems is a major issue internationally due to the pollution and nutrient enrichment of water ways. This study will examine how a strategy of synchronising phosphorus (P) fertiliser to periods of high P demand in ryegrass (Lolium perenne) may be used to improve the efficiency of P uptake and thereby reduce P losses in surface run ....Synchronising phosphorus fertilisation with plant phosphorus demand: a tactic to reduce phosphorus transfer from land to water. Phosphorus loss from intensive pasture systems is a major issue internationally due to the pollution and nutrient enrichment of water ways. This study will examine how a strategy of synchronising phosphorus (P) fertiliser to periods of high P demand in ryegrass (Lolium perenne) may be used to improve the efficiency of P uptake and thereby reduce P losses in surface runoff. Simple models will be used to identify the key risk factors associated with surface P loss in order to improve the sustainability of P fertiliser use in pasture systems.Read moreRead less
Ecosystem restoration of bauxite-processing residue sand disposal areas in Western Australia: Important biogeochemical processes and effective fertilisation strategies. Alumina production is one of Australia's most important mining activities. Residue from bauxite-processing must be managed appropriately to minimise detrimental impacts on the surrounding environment. The location of Alcoa's WA Refineries in environmentally- and community- sensitive areas necessitates a detailed understanding of ....Ecosystem restoration of bauxite-processing residue sand disposal areas in Western Australia: Important biogeochemical processes and effective fertilisation strategies. Alumina production is one of Australia's most important mining activities. Residue from bauxite-processing must be managed appropriately to minimise detrimental impacts on the surrounding environment. The location of Alcoa's WA Refineries in environmentally- and community- sensitive areas necessitates a detailed understanding of residue disposal area (RDA) management. Currently little is known about the biogeochemical cycling of nitrogen, phosphorus and carbon in the residue sand despite its importance for sustainable rehabilitation practice. Findings from this project are critical for developing improved fertilisation strategies and protocols for ecosystem restoration of RDAs, which will be applicable both in Australia and overseas. Read moreRead less
Below-ground processes: filling the missing gap in predicting the response of grain production to elevated carbon dioxide (CO2) in southern Australia. Climate change is expected to have major impacts on the Australian grains industry, which is worth $7 billion annually. Although increases in atmospheric carbon dioxide (CO2) are expected to initially increase plant productivity, the realisation of these productivity benefits is expected to be limited by water and/or nutrient deficiencies. Given o ....Below-ground processes: filling the missing gap in predicting the response of grain production to elevated carbon dioxide (CO2) in southern Australia. Climate change is expected to have major impacts on the Australian grains industry, which is worth $7 billion annually. Although increases in atmospheric carbon dioxide (CO2) are expected to initially increase plant productivity, the realisation of these productivity benefits is expected to be limited by water and/or nutrient deficiencies. Given our low rainfall and infertile soils, there is considerable uncertainty about the applicability of overseas data used to model how Australian grain systems will respond to climate change (especially elevated CO2). This project will lead to better predictions of the impact of climate change on Australian grain systems so that appropriate adaptation responses can be developed by government and industry.Read moreRead less